New MK3S+ Extruder thumping and under extrusion
Hi all,
Hoping that I can find a fix to this and get started printing again!
I have a new MK3S+ that worked for a week or two, then I started experiencing under extrusion and a strange relatively subtle thumping sound that I believe is coming from the extruder. PLA has basically stopped working, and now PETG has also started showing signs of under extrusion.
I've tried following along with most of the posts I could find related to this topic including the below to no success. I've got a new nozzle on the way but am wondering if that thumping noise could be the culprit as I have tried most other solutions that I have heard of. See video and pictures for examples
Observations:
- Some metal dust from extruder gears grinding, likely from idler spring over tightening
- Under extrusion from first layer
- Thumping noise both with and without filament
- Eventual clicking and filament grinding/ slipping on longer prints
- Extruder gear seems to rotate but I'm not sure if it is rotating "Properly"
Fixes tried:
https://help.prusa3d.com/article/under-extrusion_2007
- Changing temp +/-
- Cleaning nozzle
- Checking extruder gear alignment on shaft
- Tightening idler screw/ spring
- Cold pulls
- Centered extruder gear and ensure grub screw was tightened
- Experimental menu for heat creep ( https://help.prusa3d.com/article/experimental-menu-mk3-s-_161213)
- Some metal dust from extruder gears grinding, likely from idler spring over tightening
Check with a magnet - some filament dust can appear strikingly similar...
If definitely metal something is out of line, probably not the springs - but check the idler bearings.
The most likely error to develop over time is an improperly tightened set screw, see:
steps 9,10,32,33, *35*, 36 on https://help.prusa3d.com/guide/5-e-axis-assembly_169235
Cheerio,
RE: New MK3S+ Extruder thumping and under extrusion
Thanks so much for the reply!
I've double checked that the idler bearings are both in place and that the shaft is centered in the printed piece.
I've also verified that the set screw is tightened and on the flat part of the shaft.
What are your thoughts on the thumping noise in the video, is it possible that is causing some of the under extrusion or is that normal?
I can't judge the video properly, the field of view doesn't show enough of the X & Y axis activity - the thumping might just be a little slack in the belts slapping on change of motion.
Try heating to PETG temperatures and loading then purging PLA (just click 'no' a couple of times when it asks if the load is OK)
- then try printing PLA.
Cheerio,